JP3571409B2 - Transmission control device for automatic transmission - Google Patents

Description

【００２２】
次に、第１〜第３クラッチＣＬ１〜ＣＬ３と第１，第２ブレーキＢ１，Ｂ２の係脱制御を行うための制御装置を図２〜図４に基づいて説明する。なお、図２〜図４は制御装置の各部を示し、これら三つの図により一つの制御装置を構成している。また、各図の油路のうち、終端に丸囲みのアルファベット（Ａ〜Ｙ）が付いているものは、他の図の同じアルファベットが付いた油路と繋がっていることを意味する。さらに、図における×印はその部分がドレンされていることを意味する。
【００２３】
この制御装置には油圧ポンプ１０から作動油が供給されており、この作動油がレギュレータバルブ２０によりライン圧Ｐ１に調圧されて油路１００に送られ、図示のように供給される。
この制御装置内には、このレギュレータバルブ２０の外に、運転席のシフトレバーに繋がり運転者のマニュアル操作により作動されるマニュアルバルブ２５と、６個のソレノイドバルブＳＡ〜ＳＦと、６個の油圧作動バルブ３０，３５，４０，４５，５０，５５と、４個のアキュムレータ７１〜７４とが配設されている。ソレノイドバルブＳＡ，ＳＣ，ＳＦはノーマルオープンタイプのバルブでソレノイドが通電オフのときにはこれらバルブは開放される。一方、ソレノイドバルブＳＢ，ＳＤ，ＳＥはノーマルクローズタイプのバルブでソレノイドが通電オフのときにはこれらバルブは閉止される。
【００２４】
なお、以下においては、バルブ３０をリデューシングバルブ、バルブ３５をＬ−Ｈシフトバルブ、バルブ４０をＦＷＤ圧スイッチングバルブ、バルブ４５をＲＥＶ圧スイッチングバルブ、バルブ５０をデリバリーバルブ、バルブ５５をリリーフバルブと称する。
【００２５】
上記マニュアルバルブ２５の作動と、ソレノイドバルブＳＡ〜ＳＦの作動とに応じて各バルブが作動され、変速制御が行われる。この場合での各ソレノイドバルブの作動とこの作動に伴い設定される速度段との関係は下記表２に示すようになる。この表２におけるＯＮ，ＯＦＦはソレノイドのＯＮ，ＯＦＦを表している。なお、この表２においてはソレノイドバルブＳＦの作動は表示していないが、このソレノイドバルブＳＦはリバース速度段設定時にライン圧を増圧するときに用いるものであり、変速段設定には使用されないものであるためである。
【００２６】
【表２】

【００２７】
上記制御について、以下に説明する。
まず、シフトレバーによりＤレンジ（前進側レンジ）が設定され、マニュアルバルブ２５のスプール２６がＤ位置に移動した場合を考える。図においては、スプール２６はＮ位置にあり、右端フック部がＤ位置まで右動されてスプール２６はＤ位置に位置する。このとき、ライン圧Ｐ１を有する作動油は、油路１００から分岐する油路１０１，１０２に送られ、ＦＷＤスイッチングバルブ４０のスプール溝を通って油路１０３からマニュアルバルブ２５に送られる。そして、スプール２６の溝を介して油路１１０および１２０に送られる。なお、油路１１０はこの状態ではＲＥＶスイッチングバルブ４５において閉塞されている。
【００２８】
油路１２０に送られたライン圧Ｐ１の作動油は、分岐油路１２１，１２２，１２３，１２４，１２５を介してそれぞれソレノイドバルブＳＦ，ＳＥ，ＳＤ，ＳＢ，ＳＡに供給される。油路１２０のライン圧Ｐ１はＬ−Ｈシフトバルブ３５の右端にも作用し、このバルブ３５のスプール３６を左動させる。油路１２０の分岐油路１２６はデリバリーバルブ５０の右側に繋がり、油路１２６から分岐する油路１２７はリリーフバルブ５５の左端に繋がり、このバルブ５５のスプール５６，５７を右動させる。
【００２９】
一方、油路１０３の分岐油路１０３ａはＦＷＤスイッチングバルブ４０の右端に繋がり、ライン圧Ｐ１によりスプール４１は左方に押圧される。油路１０３の分岐油路１０４は左動されたＬ−Ｈシフトバルブ３５のスプール３６の溝を介して油路１０５に送られ、ライン圧Ｐ１をＦＷＤスイッチングバルブ４０の左側に作用させる。油路１０４の分岐油路１０６はＲＥＶスイッチングバルブ４５の右端に繋がり、ライン圧Ｐ１によりそのスプール４６を左動状態で保持させる。
また、油路１０３の分岐油路１０７はソレノイドバルブＳＣに繋がり、ソレノイドバルブＳＣにもライン圧Ｐ１が供給される。
【００３０】
以上のように、ソレノイドバルブＳＡ〜ＳＦにはそれぞれライン圧Ｐ１が供給されており、このバルブの開閉制御によりライン圧Ｐ１を有した作動油の供給制御を行うことができる。
【００３１】
ここでまず、１ＳＴ変速段を設定する場合を説明する。なお、変速段の設定では表２に示すようにソレノイドバルブＳＦは関係しないので、ここではソレノイドバルブＳＡ〜ＳＥについてのみ考える。
１ＳＴでは、表２に示すように、ソレノイドバルブＳＣがオンで、それ以外がオフであり、ソレノイドバルブＳＡのみが開放され、他のソレノイドバルブは閉止される。ソレノイドバルブＳＡが開放されると、油路１２５から油路１３０にライン圧Ｐ１が供給され、油路１３０からＤ位置に位置したマニュアルバルブスプール２６の溝を通って油路１３１にライン圧Ｐ１が供給される。
【００３２】
油路１３１の分岐油路１３１ａはリリーフバルブ５５の右端に繋がっており、ライン圧Ｐ１がリリーフバルブ５５の右端に作用する。さらに、油路１３１から分岐する油路１３２を介してライン圧Ｐ１は第１クラッチＣＬ１に供給され、第１クラッチＣＬ１が係合される。なお、このクラッチ圧ＣＬ１の変化は第１アキュムレータ７１により調整される。
【００３３】
なお、第２クラッチＣＬ２はリリーフバルブ５５（このときスプール５６，５７は右動状態）からソレノイドバルブＳＢを介してドレンに繋がり、第３クラッチＣＬ３はソレノイドバルブＳＣを介してドレンに繋がり、第１ブレーキＢ１はリリーフバルブ５５からソレノイドバルブＳＣを介してドレンに繋がり、第２ブレーキＢ２はマニュアルバルブ２５を介してドレンに繋がる。このため、第１クラッチＣＬ１のみが係合されて１ＳＴ速度段が設定される。
【００３４】
次に、２ＮＤ速度段を設定する場合を考える。このときには、ソレノイドバルブＳＤがオフからオンに切り換わり、ソレノイドバルブＳＤも開放される。これにより、油路１２３から油路１４０にライン圧Ｐ１が供給され、スプール５６，５７が右動した状態のリリーフバルブ５５から油路１４１を介して第１ブレーキＢ１にライン圧Ｐ１を有した作動油が供給される。このため、第１クラッチＣＬ１および第１ブレーキＢ１がともに係合されて２ＮＤ速度段が設定される。
【００３５】
３ＲＤ速度段を設定するときには、ソレノイドバルブＳＣがオンからオフに切り換わり、ソレノイドバルブＳＤがオフに戻される。ソレノイドバルブＳＤがオフに戻るため、第１ブレーキＢ１は開放される。ソレノイドバルブＳＣがオフに切り換わることにより、これが開放され、油路１０７からライン圧Ｐ１を有した作動油が油路１４５を介して第３クラッチＣＬ３に供給される。これにより第３クラッチＣＬ３が係合されて３ＲＤ速度段が設定される。
このとき同時に、油路１４５から分岐する油路１４６を介してライン圧Ｐ１がデリバリーバルブ５０の左側に作用し、油路１４７を介してライン圧Ｐ１がリリーフバルブ５５の右端に作用する。
【００３６】
４ＴＨ速度段を設定するときには、ソレノイドバルブＳＢをオフからオンに切換えるとともに、ソレノイドバルブＳＣをオンに戻す。ソレノイドバルブＳＣがオンに戻されるため、第３クラッチＣＬ３は解放される。一方、ソレノイドバルブＳＢがオンに切り換わることにより、ソレノイドバルブＳＢが開放され、油路１２４からライン圧Ｐ１が油路１５０，１５１に供給され、右動したスプール５６の溝から油路１５２を介して第２クラッチＣＬ２にライン圧Ｐ１が供給される。このため、第２クラッチＣＬ２が係合されて４ＴＨ速度段が設定される。
【００３７】
５ＴＨ速度段を設定するときには、ソレノイドバルブＳＡをオフからオンに切り換えるとともにソレノイドバルブＳＣをオンからオフに切り換える。ソレノイドバルブＳＡがオフからオンに切り換わると、油路１３０へのライン圧Ｐ１の供給が遮断され、且つ第１クラッチＣＬ１はソレノイドバルブＳＡを介してドレンに繋がり、第１クラッチＣＬ１は解放される。一方、ソレノイドバルブＳＣがオフに切り換えられると、上述のように第３クラッチＣＬ３が係合され、この結果５ＴＨ速度段が設定される。
【００３８】
以上のようにして各クラッチ、ブレーキの係合制御が行われるのであるが、ここで、シフトアップされる場合の係合制御を図５に示すタイムチャートと図６〜図８に示すフローチャートに基づいて説明する。図６のフローチャートに示すように、ステップＳ２では、シフト指令が出力されたか否かが判断され、出力されたと判断されると、さらにステップＳ４においてそのシフト指令がシフトアップ指令か否かが判断される。シフトアップ指令のときは、ステップＳ６においてアクセル操作によるスロットル開度θＴＨが所定開度θａよりも大きいか否かが判断され、θＴＨ＞θａと判断されるとステップＳ１０に進み、パワーオン・シフトアップ制御が行われる。一方、θＴＨ≦θａと判断されるとステップＳ６０に進み、パワーオフ・シフトアップ制御が行われる。
【００３９】
パワーオン・シフトアップ制御は、図７および図８に示すフローチャートに従って行われる。なお、ここではタイムチャートに示すように、時間ｔ０ において２速段から３速段へのシフトアップ指令が出された場合について説明する。
【００４０】
このパワーオン・シフトアップ制御では、２速段（前段）設定用のソレノイドバルブＳＤと３速段（次段）設定用のソレノイドバルブＳＣとが制御される。なお、ソレノイドバルブＳＤ、ＳＣのオン・オフおよびデューティ比を決めるための信号が、請求の範囲にいう油圧指令信号であり、タイムチャートにはこれら油圧指令信号をＳＳＤ、ＳＳＣとして示している。図７に示すソレノイドバルブＳＤの制御フローにおいては、ステップＳ１２において、シフトアップ指令が出力された直後から所定時間Ｔ１のカウントがスタートする。これと同時に、図８に示すソレノイドバルブＳＣの制御フローにおいては、ステップＳ３２において、シフトアップ指令が出力された直後から所定時間Ｔ２（＞Ｔ１）のカウントがスタートする。この間、パワーオン状態なので、タービン回転数ＮＴ はゆるやかに上昇する。
【００４１】
ソレノイドバルブＳＤ側のステップＳ１４において所定時間Ｔ１の経過が判断されると（時間ｔ１）、ステップＳ１６に進み、前段第１ステージＳＴＯ１が開始される。この前段第１ステージＳＴＯ１では、タイムチャートに示すように、ソレノイドバルブＳＤが低いデューティ比で制御される。この結果、完全係合状態にあった第１ブレーキＢ１の係合作動油圧（以下、単に油圧という）ＰＯ が徐々に低下して、第１ブレーキＢ１の係合力が弱まり、この第１ブレーキＢ１にスリップが発生する。従って、タービン回転数ＮＴ もスリップが発生していないときよりもやや大きめに（但し、吹き上がらない程度に）上昇する（タービン回転加速度αＴ 参照）。なお、制御装置内においては、入力回転センサ９ａと出力回転センサ９ｂの検出値および２速段のギヤ比から第１ブレーキＢ１の入出力回転数比（＝出力ギヤ４の回転数×２速段ギヤ比／入力軸３の回転数）ｅＣＬＯ を演算している。
【００４２】
一方、ソレノイドバルブＳＣ側のステップＳ３４において所定時間Ｔ２の経過が判断されると（時間ｔ２）、ステップＳ３６に進み、次段第１ステージＳＴＲ１が開始される。この次段第１ステージＳＴＲ１では、タイムチャートに示すように、ソレノイドバルブＳＣがオフにされる。この結果、それまで解放状態にあった第３クラッチＣＬ３にライン圧が供給されて油圧ＰR が増加し、第３クラッチＣＬ３の無効ストローク詰めが速やかに行われる。なお、制御装置内においては、各回転センサ９ａ、９ｂの検出値および３速段のギヤ比から第３クラッチＣＬ３の入出力回転数比（＝出力ギヤ４の回転数×３速段ギヤ比／入力軸３の回転数）ｅCLR も演算している。
【００４３】
第３クラッチＣＬ３の無効ストローク詰めが行われている間に、第１ブレーキＢ１の入出力回転数比がｅCLO が徐々に小さくなり、ステップＳ１８において第１所定値ｅCLO1（＜１．０）以下になったと判断されると（時間ｔ３）、ソレノイドバルブＳＤの制御はステップＳ２０に進み、前段第２ステージＳＴＯ２に移行する。この前段第２ステージＳＴＯ２では、実際の入出力回転数比ｅCLO がフィードバックされ、これを目標入出力回転数比に合わせるのに必要な第１ブレーキＢ１の油圧が演算される。ソレノイドバルブＳＤは、この演算された油圧に対応したデューティ比で制御される。なお、目標入出力回転数比は、第１ブレーキＢ１の入出力回転数比ｅCLO が１．０に近い所定範囲（第１所定値ｅCLO1よりも若干大きな入出力回転数比を下限値とする範囲）に維持されるように選択される。これにより、第１ブレーキＢ１は、微少スリップが生じている状態、即ち入力トルクにほぼ等しいトルク伝達容量を有した状態に保持される。このため、前段第２ステージＳＴＯ２が実行されている間は、タービン回転数ＮT （エンジン回転数）の吹き上がりが防止される。
【００４４】
このような前段第２ステージＳＴＯ２の制御が行われることにより、第１ブレーキＢ１の入出力回転数比ｅCLO が、第１所定値ｅCLO1より大きくなり（１．０に近づき）、ステップＳ３８において第２所定値ｅCLO2（＜１．０）以上になったと判断されると（時間ｔ４）、ソレノイドバルブＳＣの制御は、ステップＳ４０に進み、所定時間（請求の範囲にいう第１所定時間）Ｔ４のカウントをスタートさせるとともに、ステップＳ４２に進んで次段第２前期ステージＳＴＲ２ａに移行する。この際、第３クラッチＣＬ３の無効ストローク詰めはほぼ終了し、第３クラッチＣＬ３は係合直前状態又は極く僅かなトルク伝達が行われる予備係合状態になっている。
【００４５】
次段第２前期ステージＳＴＲ２ａでは、ソレノイドバルブＳＣのデューティ比を高くして、第３クラッチＣＬ３の油圧ＰR を、第３クラッチＣＬ３を係合直前状態又は予備係合状態に保持できる程度の油圧に設定する。
【００４６】
ステップＳ４４において所定時間Ｔ４の経過が判断されると（時間ｔ５）、ソレノイドバルブＳＣの制御はステップＳ４６に進み、次段第２後期ステージＳＴＲ２ｂに移行する。この次段第２後期ステージＳＴＲ２ｂでは、ソレノイドバルブＳＣのデューティ比を前期ステージＳＴＲ２ａのデューティ比から徐々に下げていき、第３クラッチＣＬ３の油圧ＰR を、係合直前状態又は予備係合状態の保持圧からほぼ一定の変化率（請求の範囲にいう第１所定変化率）で増加させる。
【００４７】
ここで、第３クラッチＣＬ３の油圧ＰR が増加するに従って、第３クラッチＣＬ３の入力トルクの分担割合が増加する一方、第１ブレーキＢ１の分担割合が低下する。このため、スリップ状態にある第１ブレーキＢ１における発熱や摩耗が抑制される。
【００４８】
こうして第１ブレーキＢ１の入出力回転数比ｅCLO は徐々に１．０に近づき、第３クラッチＣＬ３の油圧ＰR がある程度増加した時点では、タービン回転数ＮT が比較的大きく下降する一方、出力回転は慣性によってさほど低下しないため、第１ブレーキＢ１の入出力回転数比ｅCLO が１．０を超える状態になる。なお、このとき車体の加速度Ｇは若干変動する。
【００４９】
そして、ステップＳ２２およびステップＳ４８において、入出力回転数比ｅＣＬＯ が第３所定値ｅＣＬＯ３（＞１．０）以上になったと判断されると（時間ｔ６）、それぞれステップＳ２４およびステップＳ５０に進む。ステップＳ２４では、ソレノイドバルブＳＤの制御が、前段第３ステージ（請求の範囲にいう前段最終ステージ）ＳＴＯ３に移行する。前段第３ステージＳＴＯ３では、ソレノイドバルブＳＤをＯＦＦにし、第１ブレーキＢ１を解放する。
【００５０】
一方、ステップＳ５０では、ソレノイドバルブＳＣの制御が次段第３ステージＳＴＲ３に移行する。この次段第３ステージＳＴＲ３では、第３クラッチＣＬ３の入出力回転数比ｅCLR が一定変化率（請求の範囲にいう第２所定変化率）で１．０に近づくように、ソレノイドバルブＳＣがデューティ比制御される。これにより、第３クラッチＣＬ３の油圧ＰR は徐々に上昇し、タービン回転数ＮT は徐々に下降する。
【００５１】
そして、ステップＳ５２において、第３クラッチＣＬ３の入出力回転数比ｅCLR が第４所定値ｅCLR1以上になったと判断されると（時間ｔ７）、ソレノイドバルブＳＣの制御はステップＳ５４に進み、所定時間（請求の範囲にいう第２所定時間）Ｔ５のカウントがスタートされる。この間も次段第３ステージＳＴＲ３の制御が続行され、ステップＳ５６において所定時間Ｔ５の経過が判断されると、ステップＳ５８に進み、次段第４ステージ（請求の範囲にいう次段最終ステージ）ＳＴＲ４に進む。この次段第４ステージＳＴＲ４では、ソレノイドバルブＳＣをＯＦＦにし、第３クラッチＣＬ３を完全係合させる（時間ｔ８）。なお、この後、スロットル開度θTHに応じてタービン回転数ＮT は徐々に上昇する。
【００５２】
なお、入出力回転数比ｅCLR が１．０になったとの判断は容易ではないが、入出力回転数比ｅCLR が第４所定値ｅCLR1になってから、これがほぼ１．０になると予想される所定時間Ｔ５の経過により第３クラッチＣＬ３を完全係合させることによって、上記判断を行うことなく、且つショックなく第３クラッチＣＬ３を完全係合させることができる。
こうして、パワーオン状態での２速段から３速段への切換えが完了する（ステップＳ１２）。
【００５３】
一方、パワーオフ・シフトアップ制御についても、図６〜図８に示すフローチャトと同じフローチャトに従って制御される。図９のタイムチャートでは、前段第１ステージＳＴＯ１の途中においてアクセルが戻された場合を示している。この場合、パワーオン・シフトアップ制御における前段第１ステージＳＴＯ１は、アクセルが戻された時間ｔ１′をもってパワーオフ・シフトアップ制御における前段第１ステージＳＴＯ１に切り換わることになる。
【００５４】
なお、パワーオフ状態では、パワーオンの場合よりも入力トルクが小さいため、前段第１ステージＳＴＯ１および前段第２ステージＳＴＯ２におけるソレノイドバルブＳＤのデューティ比や、次段第２前期・後期ステージＳＴＲ２ａ、ＳＴＲ２ｂおよび次段第３ステージＳＴＲ３におけるソレノイドバルブＳＣのデューティ比は低めに設定される。また、各所定値の設定についても、パワーオンの場合とは若干異なる。特に、所定時間Ｔ１、Ｔ２を０（零）に設定し、シフトアップ指令が出力された後、すぐに第１ブレーキＢ１のスリップ制御（前段第１ステージＳＴＯ１）を開始し、ほぼ同時に第３クラッチの無効ストローク詰め制御（次段第１ステージＳＴＲ１）を開始するのが望ましい。このようにすれば、変速制御に必要な時間を短縮することができる。
【００５５】
そして、このように各ステージ途中において、パワーオン・シフトアップ制御とパワーオフ・シフトアップ制御との切換えが行われた場合に、切換前に係属していたステージと同じステージに係属できるように（即ち、上記切換えによって改めて切換後のフローチャートの最初から制御が開始されてしまうことがないように）する必要がある。このため、フローチャート内に、所定時間Ｔ１、Ｔ２の経過を判断したときおよび各ステージが終了する毎に、これを示すためのフラグを立てるステップを設けるのが望ましい。例えば、図９のような制御においては、所定時間Ｔ１の経過を示すフラグを立てておけば、切換えと同時に前段解放ステージＳＴＯ１が開始される一方、所定時間Ｔ２のカウントが続行される。
【００５６】
なお、上記実施例では、入出力回転数比を（出力軸回転数×ギヤ比／入力軸回転数）というように定義し、この入出力回転数比が小さな値から大きな値に変化するようにステージを構成した場合について説明したが、本発明の変速制御装置では、入出力回転数比を（入力軸回転数×ギヤ比／出力軸回転数）というように定義し、この入出力回転数比が大きな値から小さな値に変化するようにステージを構成してもよい。
【００５７】
【発明の効果】
以上説明したように、本発明の変速制御装置では、前段第１ステージによって前段係合要素にスリップが生じ始めるとほぼ同時に、次段第１ステージによる次段係合要素の無効ストローク詰めを行い、前段係合要素の入出力回転数比が第１所定値を経て第２所定値になった（無効ストローク詰めがほぼ完了した）後速やかに次段第２ステージに移行して次段係合要素の係合作動油圧を徐々に上昇させるようになっている。このため、前段係合要素のみによって入力トルクを負担するのは、次段係合要素の無効ストローク詰めが行われている短時間の間だけであり、その後は前段および次段係合要素の双方により入力トルクを分担する。したがって、従来のように全入力トルクを負担しながらスリップし続ける場合に比べて前段係合要素の発熱や摩耗が抑制される。なお、このように各係合要素の入出力回転数比を用いることにより、各係合要素の係合制御を独立して行うことができ、制御の精度を向上させることができる。
【００５８】
また、前段第２ステージに移行したとき、前段係合要素は微少スリップが生じた状態に保持される。このため、入力回転（エンジン回転）の吹き上がりを確実に防止することができる。
【００５９】
しかも、本変速制御装置では、前段係合要素の入出力回転数比が第３所定値になった後、即ち次段係合要素の係合作動油圧がある程度上昇して入力トルクの負担割合が大きくなった後に、前段最終ステージに移行して前段係合要素を解放させるとともに、次段最小ステージに移行して次段係合要素を完全係合させるようになっている。このため、次段係合要素の完全係合の際におけるショックの発生を抑えることができる。
【００６０】
さらに、次段係合要素を所定油圧に保持する油圧指令信号を第１所定時間出力してから、この次段係合要素の係合作動油圧を第１所定変化率で増加させる油圧指令信号を出力するように次段第２ステージを構成しているので、次段第１ステージから次段第２ステージに移行する際の次段係合要素の油圧変動を防止することができ、スムーズな変速制御を行うことができる。
【００６１】
また、前段第２ステージにおいて前段係合要素の入出力回転数比が第３所定値になった後、次段第３ステージに移行して次段係合要素の係合作動油圧を次段第２ステージの終了時点よりもさらに上昇させ、次段係合要素の入出力回転数比をできるだけ１．０に近づけた状態で前段最終ステージに移行して前段係合要素を解放するとともに、次段最終ステージに移行して次段係合要素を係合させるようにすれば、よりショックの少ない変速段の切換えを行うことができる。
なお、上記第３所定値を用いる代わりに、次段係合要素の入出力回転数比によりこの係合要素の係合状態を確認して前段係合要素を解放するようにしてもよい。
【００６２】
さらに、次段第３ステージにおいて次段係合要素の入出力回転数比が１．０より小さな第４所定値になったときから第２所定時間が経過したときに次段係合要素を完全係合させるようにしておき、次段係合要素の入出力回転数比が第４所定値になってからほぼ１．０になると予想される時間を第２所定時間として設定しておけば、入出力回転数比が１．０になったか否かを直接判断しなくても、ショックなく次段係合要素を完全係合させることができる。
【図面の簡単な説明】
【図１】本発明に係る変速制御装置による変速制御が行われる自動変速機の構成を示す概略図である。
【図２】本発明に係る変速制御装置を構成する油圧回路図である。
【図３】本発明に係る変速制御装置を構成する油圧回路図である。
【図４】本発明に係る変速制御装置を構成する油圧回路図である。
【図５】本発明に係る変速制御装置によるパワーオン・シフトアップ制御における各種変数の経時変化を示すグラフである。
【図６】本発明に係る変速制御装置による変速制御内容を表すフローチャートである。
【図７】本発明に係る変速制御装置による変速制御内容を表すフローチャートである。
【図８】本発明に係る変速制御装置による変速制御内容を表すフローチャートである。
【図９】本発明に係る変速制御装置によるパワーオフ・シフトアップ制御における各種変数の経時変化示すグラフである。
【符号の説明】
３ 変速機入力軸
４ 変速機出力ギヤ
１０ 油圧ポンプ
２０ レギュレータバルブ
２５ マニュアルバルブ
３０ リデューシングバルブ
３５ Ｌ−Ｈシフトバルブ
４０ ＦＷＤスイッチングバルブ
４５ ＲＥＶスイッチングバルブ
５０ デリバリーバルブ
５５ リリーフバルブ[0001]
[Industrial applications]
The present invention relates to an automatic transmission used for a vehicle or the like, and more particularly, to a shift control device that controls engagement hydraulic pressure (engagement force) of a preceding engagement element and a next engagement element at the time of upshifting.
[0002]
[Prior art]
The automatic transmission is configured with a plurality of gear trains, and a plurality of power transmission paths formed by the gear trains are selected by engaging engagement elements such as clutches, brakes, and the like with hydraulic pressure, and input rotation is selected. The shift is performed. When performing a gear shift in such a transmission, the engaging element for setting the power transmission path before the gear shift (the previous engaging element) is released, and the engaging element for setting the power transmission path following the gear shift (the next engaging element) is used. (Step engaging element).
[0003]
In order to make such a shift smoothly and without a time lag, the disengagement or engagement timing of each engagement element is accurately set, and the engagement force until the engagement element is released or completely engaged is determined. It is necessary to control properly. For example, Japanese Patent Application Laid-Open No. 62-246653 discloses that after a gearshift command is issued, the engagement hydraulic pressure of a previous-stage engagement element is reduced to cause a certain degree of slip in this engagement element, while the next-stage engagement element A method has been proposed in which the invalid stroke is reduced, and then, the engagement of the next-stage engagement element is released, and the previous-stage engagement element is released, so that the engagement hydraulic pressure of the next-stage engagement element is gradually increased.
[0004]
[Problems to be solved by the invention]
However, in the case where the shift control is performed by slipping the front engagement element in this way, if the front engagement element is slipped for an excessively long time in a state where the front engagement element bears all of the input torque, the front engagement force is reduced. There is a problem that the combined element is likely to generate heat or wear.
[0005]
The present invention has been made in view of such a problem, and provides a shift control device for an automatic transmission in which shifting can be performed smoothly and without a time lag, and wear and the like of a front engagement element can be prevented as much as possible. It is aimed at.
[0006]
Means and action for solving the problem
In order to achieve the above object, in the transmission control device of the present invention, the first-stage first-stage that outputs a hydraulic command signal that quickly reduces the engagement hydraulic pressure of the first-stage engagement element, and the first-stage engagement element include: A first-stage hydraulic output command signal for controlling an engagement hydraulic pressure of the first-stage engagement element so as to maintain a slip state at an input / output rotation speed ratio (= output rotation speed / input rotation speed) within a predetermined range. The two-stage, the next-stage first stage that outputs a high-pressure hydraulic command signal required to perform the invalid stroke filling of the next-stage engagement element, and the engagement hydraulic pressure of the next-stage engagement element from a predetermined hydraulic pressure A second stage for outputting a hydraulic command signal for increasing at a first predetermined change rate, a last stage for outputting a hydraulic command signal for releasing the previous engaging element, and a next stage engaging element are engaged. Output such a hydraulic command signal It is provided a stage final stage. Then, in this shift control device, after the output of the upshift command, the first stage of the previous stage and the next stage is started, and when the input / output rotation ratio of the first stage engagement element reaches the first predetermined value in the first stage of the first stage. In addition, the first stage is shifted from the first stage to the second stage, and when the input / output rotation ratio of the front engagement element becomes the second predetermined value larger than the first predetermined value in the second stage, the next stage is performed. The first stage shifts to the next second stage, and after the input / output rotation ratio of the previous engagement element has reached the third predetermined value larger than the second predetermined value in the second previous stage, the previous second stage is shifted to the previous stage. The process shifts to the final stage, and shifts from the second stage to the final stage.
[0007]
Further, in the control by the shift control device, the first predetermined value is set to a value smaller than 1.0, the second predetermined value is set to a value larger than the first predetermined value and smaller than 1.0, The predetermined value is set to a value larger than 1.0 .
[0008]
According to such a shift control device, almost immediately when slippage occurs in the previous-stage engagement element by the first-stage first stage, the ineffective stroke of the next-stage engagement element is reduced by the next-stage first stage. After the input / output rotational speed ratio of the element reaches the second predetermined value after passing the first predetermined value (the invalid stroke reduction is almost completed), the operation immediately shifts to the next second stage to engage the next stage engagement element. Dynamic hydraulic pressure increases. For this reason, the input torque is borne only by the previous-stage engagement element only during the short time period during which the invalid stroke of the next-stage engagement element is reduced. To share the input torque. Therefore, abrasion of the front-stage engagement element is prevented as compared with the case where the vehicle continues to slip while bearing the entire input torque. Note that, in the state of shifting to the second stage of the previous stage, the front stage engaging element is maintained in a state in which a slight slip has occurred (a state in which the input / output rotational speed ratio is within a predetermined range close to 1.0). (Engine rotation) is reliably prevented from rising.
[0009]
Moreover, after the input / output rotational speed ratio of the previous-stage engagement element has reached the third predetermined value, that is, after the engagement hydraulic oil pressure of the next-stage engagement element has increased to some extent and the input torque share ratio has increased, Since the process shifts to the preceding final stage to release the former engaging element, and shifts to the next final stage to engage the next engaging element, it is possible to suppress the occurrence of a shift shock.
[0010]
Further, in the control by the shift control device, the next-stage second stage outputs a hydraulic command signal for maintaining the engagement operating oil pressure of the next-stage engagement element at the predetermined hydraulic pressure for the first predetermined time, and then outputs the signal to the next stage. It is configured to output a hydraulic pressure command signal for increasing the engagement hydraulic pressure of the step engagement element at a first predetermined change rate .
[0011]
If it is attempted to raise the hydraulic command signal again immediately after the output of the high-pressure hydraulic command signal in the first stage of the next stage is stopped, the engagement hydraulic pressure of the next-stage engaging element is temporarily reduced due to a response delay of the hydraulic control means or the like. May be greatly reduced. For this reason, after the output of the high-pressure hydraulic command signal is cut off as described above, the hydraulic command signal is lowered for a short time (first predetermined time) (just before the next-stage engaging element is engaged or a very slight torque). (To the extent that the engagement hydraulic pressure necessary to maintain the transmission state is generated), it is possible to relatively smoothly increase the engagement hydraulic pressure of the next-stage engagement element thereafter. it can.
[0012]
In addition, the next stage output unit outputs a hydraulic pressure command signal for controlling the engagement hydraulic pressure of the next stage engagement element so that the input / output rotation ratio of the next stage engagement element approaches 1.0 at the second predetermined change rate. Three stages are provided, and when the input / output rotation ratio of the previous stage engaging element reaches the third predetermined value in the second stage of the previous stage, the stage shifts from the second stage of the next stage to the third stage of the next stage. You may make it shift to a stage.
[0013]
According to this, the engagement hydraulic pressure of the next-stage engagement element is further increased from the end point of the next-stage second stage, and the input / output rotation speed ratio of the next-stage engagement element is brought closer to the engagement start state. Thus, the first-stage engagement element can be released and the next-stage engagement element can be engaged. Therefore, the shift shock is further reduced.
[0014]
Further, when the input / output rotation ratio of the next-stage engagement element has reached a fourth predetermined value smaller than 1.0 in the next-stage third stage, when the second predetermined time has elapsed, the next-stage engagement element is activated. A hydraulic command signal for complete engagement may be output.
[0015]
In this case, if the time that the input / output rotational speed ratio of the next-stage engagement element is expected to become approximately 1.0 after reaching the fourth predetermined value is set as the second predetermined time, the input / output rotational speed ratio can be set. Can be engaged without shock without directly judging whether or not has become 1.0. Further, even if the change rate of the input / output rotation ratio fluctuates with a change in the input torque caused by the driver slightly returning the accelerator, the next-stage engagement element can be smoothly engaged.
[0016]
【Example】
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a power transmission system configuration of an automatic transmission in which a shift control is performed by a shift control device according to the present invention.
This transmission has a torque converter 2 connected to an engine output shaft 1 and a transmission input shaft 3 connected to a turbine shaft of the torque converter 2, and a planetary transmission mechanism is mounted on the input shaft 3. It is arranged.
[0017]
This transmission mechanism has first, second and third planetary gear trains G1, G2, G3 arranged in parallel on the transmission input shaft 3. Each of the gear trains includes first to third sun gears S1, S2, and S3 located at the center, and first to third planetary pinions P1 that mesh with the first to third sun gears and revolve while rotating around them. , P2, and P3, first to third carriers C1, C2, and C3 that rotatably hold the pinion and rotate the same as the revolution of the pinion, and first to third carriers that have internal teeth that mesh with the pinion. It is composed of ring gears R1, R2, R3.
Note that the first and second planetary gear trains G1 and G2 are double pinion type planetary gear trains, and the first and second pinions P1 and P2 are respectively composed of two pinions P11, P12 and P21 and P22 as shown. Is done.
[0018]
The first sun gear S1 is always connected to the input shaft 3, and the first carrier C1 can be fixedly held by the first brake B1 and is always connected to the second sun gear S2. The first ring gear R1 is removably connected to the first carrier C1 and the second sun gear S2 via a third clutch CL3. The second carrier C2 and the third carrier C3 are always connected and are always connected to the output gear 4. The second ring gear R2 and the third ring gear R3 are always connected, can be fixedly held by the second brake B2, and are connected to the case via the one-way clutch B3 to prevent rotation in the forward drive direction. Only the brake action is produced, and these are removably connected to the input shaft 3 via the second clutch CL2. The third sun gear S3 is detachably connected to the input shaft via the first clutch CL1.
Further, an input rotation sensor 9a and an output rotation sensor 9b are provided as shown in the figure.
[0019]
In the transmission configured as described above, by performing the disengagement control of the first to third clutches CL1 to CL3 and the first and second brakes B1 and B2, it is possible to perform the setting of the shift speed and the shift control. . Specifically, by performing the engagement / disengagement control as shown in Table 1, the forward five speeds (1ST, 2ND, 3RD, 4TH, 5TH) and the reverse first speed (REV) can be set.
[0020]
Note that, in Table 1, the second brake B2 in 1ST is parenthesized because the 1st shift speed can be set by the action of the one-way clutch B3 without engaging the second brake B2. That is, if the first clutch CL1 is engaged, the 1st gear can be set without engaging the second brake B2. However, the one-way clutch B3 cannot tolerate the power transmission reverse to the driving side, and therefore, when the second brake B2 is in the disengaged state, 1ST is a gear position where the engine brake does not work, and the second brake B2 Is engaged, the gear position is set so that the engine brake works. Note that 1ST in the D range is a gear position where engine braking does not work.
[0021]
[Table 1]

[0022]
Next, a control device for controlling the engagement and disengagement of the first to third clutches CL1 to CL3 and the first and second brakes B1 and B2 will be described with reference to FIGS. 2 to 4 show the components of the control device, and these three figures constitute one control device. Further, among the oil passages in each drawing, those having a circled alphabet (A to Y) at the end means that they are connected to the oil passages having the same alphabet in other drawings. Further, the mark x in the figure means that the part is drained.
[0023]
The control device is supplied with hydraulic oil from a hydraulic pump 10. The hydraulic oil is regulated to a line pressure P <b> 1 by a regulator valve 20, sent to an oil passage 100, and supplied as shown.
In the control device, in addition to the regulator valve 20, a manual valve 25 which is connected to a shift lever in a driver's seat and is operated by a driver's manual operation, six solenoid valves SA to SF, and six hydraulic valves The operation valves 30, 35, 40, 45, 50, 55 and four accumulators 71 to 74 are provided. Solenoid valves SA, SC and SF are normally open type valves, and these valves are opened when the solenoid is turned off. On the other hand, the solenoid valves SB, SD, and SE are normally closed type valves, and these valves are closed when the solenoid is turned off.
[0024]
In the following, the valve 30 is a reducing valve, the valve 35 is an LH shift valve, the valve 40 is a FWD pressure switching valve, the valve 45 is a REV pressure switching valve, the valve 50 is a delivery valve, and the valve 55 is a relief valve. Name.
[0025]
Each valve is operated according to the operation of the manual valve 25 and the operation of the solenoid valves SA to SF, and the shift control is performed. The relationship between the operation of each solenoid valve in this case and the speed stage set in accordance with this operation is as shown in Table 2 below. ON and OFF in Table 2 represent ON and OFF of the solenoid. Although the operation of the solenoid valve SF is not shown in Table 2, this solenoid valve SF is used when increasing the line pressure when setting the reverse speed, and is not used for setting the speed. Because there is.
[0026]
[Table 2]

[0027]
The above control will be described below.
First, consider a case where the D range (forward range) is set by the shift lever and the spool 26 of the manual valve 25 moves to the D position. In the drawing, the spool 26 is at the N position, the right end hook portion is moved rightward to the D position, and the spool 26 is located at the D position. At this time, the hydraulic oil having the line pressure P1 is sent to the oil passages 101 and 102 branched from the oil passage 100, and is sent from the oil passage 103 to the manual valve 25 through the spool groove of the FWD switching valve 40. Then, the oil is sent to the oil passages 110 and 120 through the groove of the spool 26. The oil passage 110 is closed by the REV switching valve 45 in this state.
[0028]
The hydraulic oil having the line pressure P1 sent to the oil passage 120 is supplied to the solenoid valves SF, SE, SD, SB, and SA via branch oil passages 121, 122, 123, 124, and 125, respectively. The line pressure P1 of the oil passage 120 also acts on the right end of the L-H shift valve 35, and moves the spool 36 of this valve 35 to the left. The branch oil passage 126 of the oil passage 120 is connected to the right side of the delivery valve 50, and the oil passage 127 branched from the oil passage 126 is connected to the left end of the relief valve 55, and the spools 56 and 57 of the valve 55 are moved rightward.
[0029]
On the other hand, the branch oil passage 103a of the oil passage 103 is connected to the right end of the FWD switching valve 40, and the spool 41 is pressed leftward by the line pressure P1. The branch oil passage 104 of the oil passage 103 is sent to the oil passage 105 via the groove of the spool 36 of the L-H shift valve 35 that has been moved leftward, and causes the line pressure P1 to act on the left side of the FWD switching valve 40. The branch oil passage 106 of the oil passage 104 is connected to the right end of the REV switching valve 45, and holds the spool 46 in a left-moving state by the line pressure P1.
The branch oil passage 107 of the oil passage 103 is connected to the solenoid valve SC, and the line pressure P1 is also supplied to the solenoid valve SC.
[0030]
As described above, the line pressure P1 is supplied to each of the solenoid valves SA to SF, and the supply control of the hydraulic oil having the line pressure P1 can be performed by controlling the opening and closing of these valves.
[0031]
Here, first, the case of setting the 1st gear position will be described. Note that, as shown in Table 2, the solenoid valves SF are not involved in setting the shift speed, so here, only the solenoid valves SA to SE will be considered.
In 1ST, as shown in Table 2, the solenoid valve SC is on, the others are off, only the solenoid valve SA is opened, and the other solenoid valves are closed. When the solenoid valve SA is opened, the line pressure P1 is supplied from the oil passage 125 to the oil passage 130, and the line pressure P1 is supplied from the oil passage 130 to the oil passage 131 through the groove of the manual valve spool 26 located at the D position. Supplied.
[0032]
The branch oil passage 131a of the oil passage 131 is connected to the right end of the relief valve 55, and the line pressure P1 acts on the right end of the relief valve 55. Further, the line pressure P1 is supplied to the first clutch CL1 via the oil passage 132 branched from the oil passage 131, and the first clutch CL1 is engaged. The change in the clutch pressure CL1 is adjusted by the first accumulator 71.
[0033]
Note that the second clutch CL2 is connected to the drain from the relief valve 55 (at this time, the spools 56 and 57 are in the right-moving state) via the solenoid valve SB, the third clutch CL3 is connected to the drain via the solenoid valve SC, and the first clutch CL3 is connected to the drain. The brake B1 is connected to the drain from the relief valve 55 via the solenoid valve SC, and the second brake B2 is connected to the drain via the manual valve 25. Therefore, only the first clutch CL1 is engaged, and the 1st speed stage is set.
[0034]
Next, a case where a 2ND speed stage is set will be considered. At this time, the solenoid valve SD switches from off to on, and the solenoid valve SD is also opened. Accordingly, the line pressure P1 is supplied from the oil passage 123 to the oil passage 140, and the first brake B1 has the line pressure P1 via the oil passage 141 from the relief valve 55 in a state where the spools 56 and 57 are moved to the right. Oil is supplied. Therefore, the first clutch CL1 and the first brake B1 are both engaged, and the 2ND speed stage is set.
[0035]
When setting the 3RD speed stage, the solenoid valve SC is switched from ON to OFF, and the solenoid valve SD is returned to OFF. Since the solenoid valve SD returns to off, the first brake B1 is released. When the solenoid valve SC is turned off, it is opened, and the hydraulic oil having the line pressure P1 is supplied from the oil passage 107 to the third clutch CL3 via the oil passage 145. As a result, the third clutch CL3 is engaged, and the 3RD speed stage is set.
At the same time, the line pressure P1 acts on the left side of the delivery valve 50 via the oil passage 146 branched from the oil passage 145, and the line pressure P1 acts on the right end of the relief valve 55 via the oil passage 147.
[0036]
When setting the 4TH speed stage, the solenoid valve SB is switched from off to on and the solenoid valve SC is turned back on. Since the solenoid valve SC is turned back on, the third clutch CL3 is released. On the other hand, when the solenoid valve SB is turned on, the solenoid valve SB is opened, the line pressure P1 is supplied to the oil passages 150 and 151 from the oil passage 124, and the oil pressure passes through the oil passage 152 from the groove of the spool 56 that has moved rightward. Thus, the line pressure P1 is supplied to the second clutch CL2. Thus, the second clutch CL2 is engaged, and the 4TH speed stage is set.
[0037]
When setting the 5TH speed stage, the solenoid valve SA is switched from off to on and the solenoid valve SC is switched from on to off. When the solenoid valve SA is switched from off to on, the supply of the line pressure P1 to the oil passage 130 is cut off, the first clutch CL1 is connected to the drain via the solenoid valve SA, and the first clutch CL1 is released. . On the other hand, when the solenoid valve SC is turned off, the third clutch CL3 is engaged as described above, and as a result, the 5TH speed stage is set.
[0038]
The engagement control of each clutch and brake is performed as described above. Here, the engagement control in the case of shifting up is performed based on the time chart shown in FIG. 5 and the flowcharts shown in FIGS. Will be explained. As shown in the flowchart of FIG. 6, in step S2, it is determined whether or not a shift command has been output. When it is determined that the shift command has been output, it is further determined in step S4 whether or not the shift command is a shift-up command. You. In the case of a shift-up command, it is determined in step S6 whether or not the throttle opening θTH due to the accelerator operation is greater than a predetermined opening θa. If it is determined that θTH> θa, the process proceeds to step S10, where power-on shift-up is performed. Control is performed. On the other hand, if it is determined that θTH ≦ θa, the process proceeds to step S60, where power-off / shift-up control is performed.
[0039]
The power-on shift-up control is performed according to the flowcharts shown in FIGS. Here, as shown in the time chart, a case will be described in which a shift-up command from the second gear to the third gear is issued at time t0.
[0040]
In the power-on shift-up control, a solenoid valve SD for setting a second speed (previous stage) and a solenoid valve SC for setting a third speed (next stage) are controlled. The signals for determining the ON / OFF of the solenoid valves SD and SC and the duty ratio are hydraulic command signals referred to in the claims, and these hydraulic command signals are shown as SSD and SSC in the time chart. In the control flow of the solenoid valve SD shown in FIG. 7, in step S12, counting of the predetermined time T1 starts immediately after the output of the upshift command. At the same time, in the control flow of the solenoid valve SC shown in FIG. 8, in step S32, counting of the predetermined time T2 (> T1) starts immediately after the output of the upshift command. During this time, since the power is on, the turbine rotational speed NT gradually increases.
[0041]
When it is determined in step S14 on the solenoid valve SD side that the predetermined time T1 has elapsed (time t1), the process proceeds to step S16, and the first stage STO1 in the preceding stage is started. In the preceding first stage STO1, the solenoid valve SD is controlled at a low duty ratio as shown in the time chart. As a result, the engagement hydraulic pressure (hereinafter simply referred to as hydraulic pressure) PO of the first brake B1 in the fully engaged state gradually decreases, and the engagement force of the first brake B1 weakens. Slip occurs. Accordingly, the turbine rotational speed NT rises slightly (but not so much as to blow up) as compared with the case where no slip occurs (see turbine rotational acceleration αT). In the control device, the input / output rotation ratio of the first brake B1 (= the rotation speed of the output gear 4 × the second speed) is determined based on the detection values of the input rotation sensor 9a and the output rotation sensor 9b and the gear ratio of the second speed. (Gear ratio / rotation speed of input shaft 3) eCLO is calculated.
[0042]
On the other hand, if it is determined in step S34 on the solenoid valve SC side that the predetermined time T2 has elapsed (time t2), the process proceeds to step S36, and the next first stage STR1 is started. In the next first stage STR1, as shown in the time chart, the solenoid valve SC is turned off. As a result, the line pressure is supplied to the third clutch CL3 which has been in the disengaged state, the hydraulic pressure PR increases, and the invalid stroke of the third clutch CL3 is quickly filled. In the control device, the input / output rotational speed ratio of the third clutch CL3 (= the rotational speed of the output gear 4 × the gear ratio of the third speed stage /) is determined from the detected values of the rotation sensors 9a and 9b and the gear ratio of the third speed stage. The rotation speed eCLR of the input shaft 3 is also calculated.
[0043]
While the ineffective stroke of the third clutch CL3 is being performed, the input / output speed ratio eCLO of the first brake B1 gradually decreases, and in step S18, it becomes equal to or less than the first predetermined value eCLO1 (<1.0). If it is determined that the time has come (time t3), the control of the solenoid valve SD advances to step S20, and shifts to the preceding second stage STO2. In the preceding second stage STO2, the actual input / output rotation speed ratio eCLO is fed back, and the hydraulic pressure of the first brake B1 required to match this to the target input / output rotation speed ratio is calculated. The solenoid valve SD is controlled at a duty ratio corresponding to the calculated hydraulic pressure. The target input / output speed ratio is a predetermined range in which the input / output speed ratio eCLO of the first brake B1 is close to 1.0 (a range in which the input / output speed ratio slightly larger than the first predetermined value eCLO1 is the lower limit). ). As a result, the first brake B1 is maintained in a state in which a slight slip has occurred, that is, in a state having a torque transmission capacity substantially equal to the input torque. For this reason, during the execution of the former second stage STO2, the turbine speed NT (engine speed) is prevented from rising.
[0044]
By performing such control of the preceding second stage STO2, the input / output rotational speed ratio eCLO of the first brake B1 becomes larger than the first predetermined value eCLO1 (approaching 1.0), and the second speed is increased in step S38. If it is determined that the predetermined value eCLO2 (<1.0) or more has been reached (time t4), the control of the solenoid valve SC proceeds to step S40, and counts a predetermined time (first predetermined time in claims) T4. At the same time, the process proceeds to step S42 to shift to the next second-stage first-half stage STR2a. At this time, the filling of the invalid stroke of the third clutch CL3 is almost finished, and the third clutch CL3 is in a state immediately before engagement or in a preliminary engagement state in which a very small amount of torque is transmitted.
[0045]
In the next stage the second year stage STR2a, by increasing the duty ratio of the solenoid valve SC, the hydraulic pressure PR of the third clutch CL3, the hydraulic enough to hold a third clutch CL3 into engagement state immediately before or pre-engagement state Set.
[0046]
If it is determined in step S44 that the predetermined time T4 has elapsed (time t5), the control of the solenoid valve SC proceeds to step S46, and shifts to the next second stage STR2b. In the next second stage STR2b, the duty ratio of the solenoid valve SC is gradually reduced from the duty ratio of the first stage STR2a, and the hydraulic pressure PR of the third clutch CL3 is maintained in the state immediately before engagement or in the preliminary engagement state. The pressure is increased at a substantially constant rate of change (first predetermined rate of change in claims).
[0047]
Here, according to the hydraulic pressure PR of the third clutch CL3 increases, while the distribution ratio of the input torque of the third clutch CL3 increases, distribution ratio of the first brake B1 is lowered. Therefore, heat generation and wear in the first brake B1 in the slip state are suppressed.
[0048]
In this way, the input / output rotational speed ratio eCLO of the first brake B1 gradually approaches 1.0, and when the hydraulic pressure PR of the third clutch CL3 increases to some extent, the turbine rotational speed NT decreases relatively largely, while the output rotational speed decreases. Since the inertia does not significantly decrease, the input / output rotational speed ratio eCLO of the first brake B1 exceeds 1.0. At this time, the acceleration G of the vehicle body slightly changes.
[0049]
When it is determined in step S22 and step S48 that the input / output rotation speed ratio eCLO has become equal to or greater than the third predetermined value eCLO3 (> 1.0) (time t6), the process proceeds to step S24 and step S50, respectively. In step S24, the control of the solenoid valve SD shifts to the third stage of the preceding stage (the last stage of the preceding stage) STO3. In the preceding third stage STO3, the solenoid valve SD is turned off and the first brake B1 is released.
[0050]
On the other hand, in step S50, the control of the solenoid valve SC shifts to the next third stage STR3. In the next third stage STR3, the duty ratio of the solenoid valve SC is set so that the input / output rotational speed ratio eCLR of the third clutch CL3 approaches 1.0 at a constant rate of change (a second predetermined rate of change in the claims). Ratio controlled. Thus, the hydraulic pressure PR of the third clutch CL3 gradually increases, and the turbine speed NT gradually decreases.
[0051]
When it is determined in step S52 that the input / output rotation speed ratio eCLR of the third clutch CL3 has become equal to or greater than the fourth predetermined value eCLR1 (time t7), the control of the solenoid valve SC proceeds to step S54, where the control proceeds to step S54. The count of the second predetermined time (T5) in the claims is started. During this time, the control of the next-stage third stage STR3 is continued. If it is determined in step S56 that the predetermined time T5 has elapsed, the process proceeds to step S58, and the next-stage fourth stage (the next-stage final stage in the claims) STR4 Proceed to. In the next fourth stage STR4, the solenoid valve SC is turned off and the third clutch CL3 is completely engaged (time t8). Thereafter, the turbine speed NT gradually increases in accordance with the throttle opening θTH.
[0052]
Although it is not easy to determine that the input / output rotation speed ratio eCLR has become 1.0, it is expected that the input / output rotation speed ratio eCLR will become approximately 1.0 after the input / output rotation speed ratio eCLR becomes the fourth predetermined value eCLR1. by completely engage the third clutch CL3 with the lapse of a predetermined time period T5, without performing the determination, and the third clutch CL3 no shock can be fully engaged.
Thus, the switching from the second gear to the third gear in the power-on state is completed (step S12).
[0053]
On the other hand, the power-off shift-up control is also controlled according to the same flowcharts as those shown in FIGS. The time chart of FIG. 9 shows a case where the accelerator is returned in the middle of the preceding first stage STO1. In this case, the first stage STO1 in the previous stage in the power-on shift-up control is switched to the first stage STO1 in the first stage in the power-off shift-up control at the time t1 'when the accelerator is returned.
[0054]
In the power-off state, the input torque is smaller than that in the power-on state. And the duty ratio of the solenoid valve SC in the next third stage STR3 is set lower. Also, the setting of each predetermined value is slightly different from the case of power-on. In particular, after the predetermined times T1 and T2 are set to 0 (zero) and the upshift command is output, the slip control of the first brake B1 (the first-stage first stage STO1) is started immediately, and almost simultaneously with the third clutch B1. It is desirable to start the invalid stroke filling control (the next stage first stage STR1). In this way, the time required for the shift control can be reduced.
[0055]
Then, when the switching between the power-on shift-up control and the power-off shift-up control is performed in the middle of each stage, it is possible to engage the same stage as the stage engaged before the switching ( That is, it is necessary to prevent the control from starting again from the beginning of the flowchart after the switching by the above switching). For this reason, it is desirable to provide a step in the flowchart for setting a flag for indicating the elapse of the predetermined times T1 and T2 and each time each stage ends. For example, in the control as shown in FIG. 9, if a flag indicating the elapse of the predetermined time T1 is set, the pre- release stage STO1 is started simultaneously with the switching, and the counting of the predetermined time T2 is continued.
[0056]
In the above embodiment, the input / output rotation ratio is defined as (output shaft rotation speed × gear ratio / input shaft rotation speed), and the input / output rotation ratio is changed from a small value to a large value. Although the case where the stage is configured has been described, in the transmission control device of the present invention, the input / output rotation ratio is defined as (input shaft rotation speed × gear ratio / output shaft rotation speed). The stage may be configured such that changes from a large value to a small value.
[0057]
【The invention's effect】
As described above, in the speed change control device of the present invention, almost immediately at the same time when the first stage of the previous stage begins to slip on the former stage engagement element, the next stage first stage performs the reduction of the invalid stroke of the next stage engagement element, After the input / output rotational speed ratio of the previous stage engagement element has reached the second predetermined value after passing through the first predetermined value (invalid stroke reduction is almost completed), the process immediately shifts to the next stage second stage and proceeds to the next stage engagement element. Is gradually increased. For this reason, the input torque is borne only by the previous-stage engagement element only during the short time period during which the invalid stroke of the next-stage engagement element is reduced. To share the input torque. Therefore, heat generation and wear of the former-stage engagement element are suppressed as compared with the conventional case in which the vehicle continues to slip while bearing the entire input torque. By using the input / output rotational speed ratio of each engagement element in this manner, the engagement control of each engagement element can be performed independently, and the control accuracy can be improved.
[0058]
When the process proceeds to the second stage of the preceding stage, the preceding stage engaging element is maintained in a state where a slight slip has occurred. Therefore, it is possible to reliably prevent the input rotation (engine rotation) from rising.
[0059]
Moreover, in the present shift control device, after the input / output rotation ratio of the previous-stage engagement element has reached the third predetermined value, that is, the engagement hydraulic pressure of the next-stage engagement element has increased to some extent, and the input torque share ratio has been reduced. After the size becomes larger, the process shifts to the last stage of the previous stage to release the previous stage engaging element, and shifts to the minimum stage of the next stage to completely engage the next stage engaging element. For this reason, it is possible to suppress the occurrence of a shock when the next-stage engagement element is completely engaged.
[0060]
Further, after outputting a hydraulic pressure command signal for holding the next-stage engagement element at a predetermined hydraulic pressure for a first predetermined time, a hydraulic command signal for increasing the engagement operating hydraulic pressure of the next-stage engagement element at a first predetermined change rate is output. Since the next-stage second stage is configured to output the output, it is possible to prevent a change in hydraulic pressure of the next-stage engagement element at the time of transition from the next-stage first stage to the next-stage second stage, and to achieve a smooth shift. Control can be performed.
[0061]
Further, after the input / output rotation speed ratio of the front-stage engagement element in the second stage of the front-stage reaches a third predetermined value, the process proceeds to the third stage of the next stage to reduce the engagement hydraulic pressure of the next-stage engagement element to the next-stage third stage. The stage is further raised from the end of the two stages, the input / output rotation ratio of the next stage engaging element is brought as close as possible to 1.0, and the process shifts to the last stage of the previous stage to release the former stage engaging element. By shifting to the final stage and engaging the next stage engaging element, it is possible to switch gears with less shock.
Instead of using the third predetermined value, the engagement state of this engagement element may be confirmed based on the input / output rotation ratio of the next engagement element, and the previous engagement element may be released.
[0062]
Further, when the input / output rotation ratio of the next-stage engagement element in the next-stage third stage reaches a fourth predetermined value smaller than 1.0, the second-stage engagement element is completely removed when a second predetermined time has elapsed. If the input / output rotational speed ratio of the next-stage engagement element is set to the fourth predetermined value and is expected to become approximately 1.0 after the engagement is set as the second predetermined time, The next-stage engagement element can be completely engaged without a shock without directly determining whether the input / output rotation speed ratio has become 1.0.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a configuration of an automatic transmission in which a shift control is performed by a shift control device according to the present invention.
FIG. 2 is a hydraulic circuit diagram of a transmission control device according to the present invention.
FIG. 3 is a hydraulic circuit diagram of a transmission control device according to the present invention.
FIG. 4 is a hydraulic circuit diagram of the transmission control device according to the present invention.
FIG. 5 is a graph showing changes over time of various variables in power-on shift-up control by the shift control device according to the present invention.
FIG. 6 is a flowchart showing shift control contents by a shift control device according to the present invention.
FIG. 7 is a flowchart showing shift control contents by a shift control device according to the present invention.
FIG. 8 is a flowchart showing shift control contents by a shift control device according to the present invention.
FIG. 9 is a graph showing changes over time of various variables in power-off / upshift control by the shift control device according to the present invention.
[Explanation of symbols]
3 Transmission Input Shaft 4 Transmission Output Gear 10 Hydraulic Pump 20 Regulator Valve 25 Manual Valve 30 Reducing Valve 35 LH Shift Valve 40 FWD Switching Valve 45 REV Switching Valve 50 Delivery Valve 55 Relief Valve

Claims (3)

A plurality of power transmission paths formed between the input / output members, a plurality of engagement elements for selectively setting the power transmission paths, and an engagement hydraulic pressure of the engagement elements controlled in accordance with a hydraulic command signal. From the previous stage to the next stage by disengaging the previous stage engagement element and engaging the next stage engagement element among the plurality of engagement elements based on a predetermined shift-up command. In a shift control device for an automatic transmission that performs a shift-up control of
A first-stage first-stage that outputs a hydraulic command signal that quickly reduces the engagement hydraulic pressure of the first-stage engagement element;
A hydraulic pressure for controlling the engagement hydraulic pressure of the front engagement element so that the front engagement element is maintained in a state of slipping at an input / output rotation speed ratio (= output rotation speed / input rotation speed) within a predetermined range. A second stage prior to outputting a command signal;
A next-stage first stage that outputs a high-pressure hydraulic command signal necessary to cause the invalid stroke of the next-stage engagement element to be reduced;
A next-stage second stage that outputs a hydraulic command signal for increasing the engagement hydraulic pressure of the next-stage engagement element from a predetermined oil pressure at a first predetermined change rate;
A pre-stage final stage that outputs a hydraulic command signal such as to release the pre-engagement element,
A next-stage final stage that outputs a hydraulic command signal such as to engage the next-stage engagement element,
After the output of the shift-up command, the first stage and the next stage are started. When the input / output rotation ratio of the front engagement element has reached a first predetermined value in the first stage, the first stage The first stage shifts to the previous second stage,
When the input / output rotation ratio of the front-stage engagement element has reached a second predetermined value that is greater than the first predetermined value in the front-stage second stage, the next-stage first stage is switched to the next-stage second stage. Migrate,
After the input / output rotation ratio of the front-stage engagement element has reached a third predetermined value larger than the second predetermined value in the front-stage second stage, the process proceeds from the front-stage second stage to the front-stage final stage, and Configured to shift from the next second stage to the next final stage ,
The first predetermined value is a value smaller than 1.0, the second predetermined value is a value larger than the first predetermined value and smaller than 1.0, and the third predetermined value is a value larger than 1.0. And
The next-stage second stage outputs a hydraulic command signal for maintaining the engagement hydraulic pressure of the next-stage engagement element at the predetermined hydraulic pressure for a first predetermined time, and then outputs the engagement hydraulic pressure of the next-stage engagement element. A shift control device for an automatic transmission, which outputs a hydraulic command signal for increasing the pressure at the first predetermined change rate . The next-stage third output unit outputs a hydraulic command signal for controlling the engagement hydraulic pressure of the next-stage engagement element so that the input / output rotation speed ratio of the next-stage engagement element approaches 1.0 at the second predetermined change rate. Has a stage,
When the input / output rotational speed ratio of the front-stage engagement element has reached the third predetermined value in the front-stage second stage, a transition is made from the next-stage second stage to the next-stage third stage, and then the next-stage shift control system for an automatic transmission according to claim 1, characterized in that the process proceeds to the final stage. When the second predetermined time has elapsed from when the input / output rotation speed ratio of the next stage engagement element has reached a fourth predetermined value smaller than 1.0 in the next stage third stage, 3. The shift control device for an automatic transmission according to claim 2 , wherein the process shifts from the first stage to the next stage.

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